Culturing in 50mL conical tubes? - (Aug/13/2007 )

Hi,
I setup midipreps today in 50mL BD Falcon conical tubes (because I didn't have enough flasks). Anyone have any negative experiences incubating e. coli in these tubes?

Thanks.

What volume of culture did you incubate in each tube? The maximum you can incubate in a 50 mL tube is around 10-20 mL. Higher than that and the culture will be severely oxygen limited and growth will probably be very poor.

There's the problem....

i did 25 and 30ml... 25 is fine, 30 ml gave me lower amount of DNA

do you have a 250ml flask?

The rule of the thumb say that your culture flask must be 5x larger then your medium volume, to get good e coli yeilds. (Although I have found that a flask 10x large is actually better)

The 40ml bugs will not grow properly in a 50 ml conical. Wait and grow them in a bigger culture flask.

Use a flask atleast 4-5x larger than culture volume.